PUB - Publikationen an der Universität Bielefeld

The 36-Ni II -containing 54-tungsto-6-silicate, [Ni 36 (OH) 18 (H 2 O) 36 (SiW 9 O 34 ) 6 ] 6- ( Ni 36 ) was synthesized by a simple one-pot reaction of the Ni 2 -pivalate complex [Ni 2 ( mu -OH 2 )(O 2 CCMe 3 ) 4 (HO 2 CCMe 3 ) 4 ] with the trilacunary [SiW 9 O 34 ] 10- polyanion precursor in water and structurally characterized by a multitude of physicochemical techniques including single-crystal XRD, FT-IR, TGA, elemental analysis, magnetic and electrochemical studies. Polyanion Ni 36 comprises six equivalent {Ni II 6 SiW 9 } units which are linked by Ni-O-W' bridges forming a macrocyclic assembly. Magnetic studies demonstrated that the {Ni 6 } building blocks in Ni 36 remain magnetically intact while forming a hexagonal ring with antiferromagnetic exchange interactions between adjacent {Ni 6 } units. Electrochemical studies indicated that the first reduction is reversible and associated with the W VI/V couple, whereas the second reduction is irreversible and associated to the couple Ni II/0 . © 2021 Wiley-VCH GmbH.